We have developed a hollow fiber device with immobilized chelators for the extracorporeal removal of toxic metals from blood, in specific Aluminum (Al). This device (similar to a hemodialysis cartridge) is a novel approach to detoxification, with unique advantages over existing treatments: (1) The immobilized chelator does not enter the blood, thus danger of toxicity is minimized. (2) The device (a) functions with high efficiency, due to large concentration of chelator and extensive contact area. (b) is specific toward a given metal according to the chelator used. (3) Blood compatibility of the hollow fibers assures safety of application Safety and efficacy of the proposed device is particularly attractive as present chelator therapy for Al intoxication has potential neurotoxicity. In Phase I. we plan to finalize design of the device by selecting specific chelators for Al and testing their efficacy in vitro, using blood from patients with Al intoxication. The most effective device will be further evaluated (in Phase II) in experimental animals to assure in vivo efficacy and safety. The development of the optimal device will lead to an IDE and clinical testing in patients on chronic hemodialysis.